1. Field of the Invention
The present invention relates to an image display apparatus and, more particularly, to an image display apparatus for synthesizing one color picture from a plurality of overlapping pictures and outputting the synthesized picture.
2. Description of the Prior Art
Image display apparatus which adopt a dot-map-display system or a character block system have convectionally been known and widely used for synthesizing and outputting various pictures to be displayed on a CRT.
As is known, a picture displayed on a CRT for games is generally composed of 224 horizontal scanning lines, and each line is composed of picture elements of 288 dots. One picture of such a picture to be displayed on a CRT is therefore composed of picture elements of 288.times.224 dots, and in order to display 256 colors on the CRT, it is necessary that a color corresponds to color data of 8 bits which designate the color for each dot.